Tape storage technology provides magnetic or optical tape for storing data. The tape typically contains a plurality of longitudinal data bands, each containing a plurality of longitudinal data tracks. A head component, also referred to as a head module or tape head, is used for writing to and reading from the tape. At the top and bottom of each data band is a servo band, made up of a plurality of patterns on the tape, providing lateral location information of the head component as it writes and verifies data tracks within that band. The head component typically has a write element and a read/verify element corresponding to each data track of a data band. Each set of write and read/verify elements are, typically, statically positioned in-line with each other such that, as the tape moves in the longitudinal direction across the head component, the data track corresponding to each respective set of write and read/verify elements, passes directly beneath (or above) each element of the set in turn. As the tape moves beneath (or above) the head component, the write element writes data onto a block on the corresponding data track. As the data passes the read/verify element, the read/verify element immediately checks for errors. If any errors are detected, the block of data is rewritten further down the tape.
Overwriting and data recovery problems can be caused by small lateral tape movements which occur due to mechanical tolerances, environmental factors, and general wear of the media and of the drive mechanism. Such small lateral movements increase the risk of overwriting neighboring tracks. In track-following technology, the tape head moves laterally across the width of the tape to compensate for any lateral tape movement. Special elements (servo read elements) on the tape head monitor the servo bands on the tape and detect whether the tape is moving laterally. The system will automatically move the tape head to compensate for the tape movement. During this lateral tape movement, the tape does not pass the tape head orthogonally, and this deviation from the orthogonal angle between the tape and the tape head is referred to as the skew. Additionally, because the tape head moves as a single unit, even as the tape head moves to compensate for lateral tape motion, the skew may prevent the read/verify element from verifying data written on a data track by the corresponding write element.